:root {
    --color-primary: #2563eb;
    --color-primary-dark: #1d4ed8;
    --color-accent: #7c3aed;
    --color-surface: #f5f7ff;
    --color-text: #0f172a;
    --rgb-primary: 37,99,235;
    --rgb-accent: 124,58,237;
    --radius-sm: 6px;
    --radius-md: 10px;
    --radius-lg: 18px;
    --radius-xl: 26px;
    --shadow-sm: 0 10px 22px rgba(2, 6, 23, .10);
    --shadow-md: 0 18px 44px rgba(2, 6, 23, .14);
    --shadow-lg: 0 28px 80px rgba(2, 6, 23, .20);
    --space-section: 5rem;
    --space-card: 2rem;
    --space-gap: 1.5rem;
    --transition: 0.52s cubic-bezier(.2, .8, .2, 1);
    --heading-weight: 800;
    --body-line-height: 1.7;
}

/* 基础覆盖 */
body { color: var(--color-text); line-height: var(--body-line-height); background: radial-gradient(1200px 700px at 15% 10%, rgba(var(--rgb-accent), .10) 0%, rgba(var(--rgb-primary), .06) 36%, transparent 70%), radial-gradient(900px 550px at 85% 0%, rgba(var(--rgb-primary), .10) 0%, transparent 58%), var(--color-surface); }
h1, h2, h3, h4 { font-weight: var(--heading-weight); }
section, .section { padding-top: var(--space-section); padding-bottom: var(--space-section); }
.card, [class*="card"] {
    border-radius: var(--radius-lg);
    box-shadow:
        0 1px 0 rgba(255,255,255,.85) inset,
        0 0 0 1px rgba(var(--rgb-primary), .10),
        0 14px 36px rgba(2, 6, 23, .12),
        0 34px 90px rgba(2, 6, 23, .10);
    padding: var(--space-card);
    transition: var(--transition);
    background:
        linear-gradient(180deg, rgba(255,255,255,.78) 0%, rgba(255,255,255,.58) 55%, rgba(255,255,255,.45) 100%);
}
.btn, button[class*="btn"], a[class*="btn"] {
    border-radius: var(--radius-md);
    transition: var(--transition);
    box-shadow:
        0 8px 18px rgba(2, 6, 23, .12),
        0 1px 0 rgba(255,255,255,.75) inset;
    background:
        linear-gradient(135deg, rgba(var(--rgb-primary), .95) 0%, rgba(var(--rgb-accent), .92) 55%, rgba(34,211,238,.72) 120%);
    color: #fff;
    border: 1px solid rgba(255,255,255,.22);
}
a:not([class]) { color: var(--color-primary); transition: var(--transition); text-shadow: 0 1px 0 rgba(255,255,255,.45); }

/* ========== Section Layout Variants ========== */

/* news: featured-top */
/* 首篇横跨全宽 */
                .news-grid { display: grid; grid-template-columns: repeat(3, 1fr); gap: var(--space-gap); }
                .news-grid > *:first-child { grid-column: span 3; }

/* features: grid-4 */
.feature-list { display: grid; grid-template-columns: repeat(4, 1fr); gap: var(--space-gap); }

/* hero: centered */
.hero-content { text-align: center; max-width: 800px; margin: 0 auto; }

/* testimonials: stacked */
/* 垂直堆叠 */
                .testimonial-list { display: flex; flex-direction: column; gap: var(--space-gap); max-width: 720px; margin: 0 auto; }

/* partners: grid-6 */
.partner-grid { display: grid; grid-template-columns: repeat(6, 1fr); gap: var(--space-gap); align-items: center; }

/* faq: with-sidebar */
/* FAQ 左 + 联系信息右 */
                .faq-wrapper { display: grid; grid-template-columns: 2fr 1fr; gap: 2rem; }

/* stats: grid-3 */
.stats-grid { display: grid; grid-template-columns: repeat(3, 1fr); gap: var(--space-gap); text-align: center; }

/* cta: centered */
.cta-inner { text-align: center; max-width: 700px; margin: 0 auto; }

/* Page Layout: wide */
/* 超宽 */
            .page-main { max-width: 1400px; margin: 0 auto; }

/* 条件性装饰 */
.card:hover, [class*="card"]:hover {
    transform: translateY(-6px);
    box-shadow:
        0 1px 0 rgba(255,255,255,.92) inset,
        0 0 0 1px rgba(var(--rgb-primary), .18),
        0 24px 60px rgba(2, 6, 23, .18),
        0 54px 130px rgba(2, 6, 23, .14);
    background:
        radial-gradient(900px 220px at 20% 0%, rgba(var(--rgb-accent), .18) 0%, transparent 55%),
        radial-gradient(680px 240px at 90% 10%, rgba(var(--rgb-primary), .18) 0%, transparent 52%),
        linear-gradient(180deg, rgba(255,255,255,.86) 0%, rgba(255,255,255,.62) 55%, rgba(255,255,255,.48) 100%);
}
.card { border: 1px solid rgba(var(--rgb-primary), .12); }
header, .header, .navbar {
    box-shadow:
        0 1px 0 rgba(255,255,255,.70) inset,
        0 14px 30px rgba(2, 6, 23, .10);
    background:
        linear-gradient(180deg, rgba(255,255,255,.78) 0%, rgba(255,255,255,.58) 100%);
    border-bottom: 1px solid rgba(var(--rgb-primary), .10);
}

/* Responsive */
@media (max-width: 1024px) {
    .news-grid { grid-template-columns: repeat(2, 1fr) !important; }
    .feature-list { grid-template-columns: repeat(2, 1fr) !important; }
    .partner-grid { grid-template-columns: repeat(3, 1fr) !important; }
    .stats-grid { grid-template-columns: repeat(2, 1fr) !important; }
    .hero-inner { grid-template-columns: 1fr !important; }
}
@media (max-width: 640px) {
    :root { --space-section: 2rem; --space-card: 1rem; --space-gap: 0.75rem; }
    .news-grid { grid-template-columns: 1fr !important; }
    .feature-list { grid-template-columns: 1fr !important; }
    .faq-list { grid-template-columns: 1fr !important; }
    .testimonial-list { column-count: 1 !important; }
    .partner-grid { grid-template-columns: repeat(2, 1fr) !important; }
    .stats-grid { grid-template-columns: repeat(2, 1fr) !important; }
    .cta-inner { grid-template-columns: 1fr !important; }
}